This invention relates to a circuit for providing an intermittent drive signal of variable magnitude and frequency to a driven device and in particular to the needle assembly of a tattoo machine. The subject circuit permits the operator of the driven device to manually regulate the power and frequency of the drive signal within a pulse of variable duration during utilization of the device.
The expanding numbers of people electing to carry xe2x80x9cbody artxe2x80x9d on their anatomy has created the demand for efficient and effective equipment to imprint the desired design in an accurate manner. Typically, the process employs a tattoo machine which drives one or more components of a needle assembly in a manner which embeds dye into the user. The needle assembly may utilize a single-ended needle or a multiple-ended needle array to provide a wide variety of artistic effects and differing coloration and shading. The needle assembly includes a reservoir for the dye being used for the particular portion of the display being imprinted. At present, the moveable components of the needle assembly are driven from a dc power supply which provides a variable output in the range of 1 to 15 volts across the parallel combination of a nonlinear impedance such as a varistor and pair of series connected coils. The coils are inductively coupled to an armature which is connected to the needle assembly. The variations in the magnetic field in the coils impart the movement to the needle assembly. Variation of the power supply voltage provides the operator of the machine with the ability to vary the intensity of the motion imparted to the needle. The repetition rate of the movement of the needle is determined by the electrical characteristics of the nonlinear impedance and the coils. Thus, the frequency of the needle stroke per unit time is fixed and not under the control of the operator.
As the complexity of the images to be depicted increases, the need for increased operator control of the operation becomes more important. The effects of different coloration schemes, nonpermanent dyes and shading features have created a need for an operator to exercise control over both the intensity of the needle stroke and the frequency of the strokes during the time interval that the operator is imparting the design to the skin. Accordingly, the present invention is directed to a circuit for providing a drive signal to the driven device or needle assembly which permits the operator to establish the envelope or pulse width of a the strokes and the power and frequency of the strokes taking place within that pulse.
The present invention is directed to a circuit which permits operator control of an intermittent pulsed signal of variable magnitude and frequency to a driven device such as the needle assembly of a tatoo machine.
The circuit includes a rectifier which is coupled to the external ac supply. A series combination of an operator-variable impedance and an operator-controlled switch is coupled between the rectifier and a circuit output terminal. A circuit-controlled switch is coupled between a circuit output terminal and the rectifier with a variable oscillator providing the actuating signal to the switch. An operator-variable frequency controller is coupled to the variable oscillator to permit adjustment of the frequency of the actuating signal.
In operation, the operator-controlled switch establishes the pulse width or interval during which the operator will be making an imprint. The variable impedance enables the operator to control the voltage and the intensity of the movement of the needle. The adjustment of the frequency controller allows the operator to select the number of needle strokes within the pulse width. Thus, the operator has control of the three functions of the driven device needed to imprint complex patterns with varying visual characteristics.
Further features and advantages of the invention will become more readily apparent from the following detailed description of a preferred embodiment when taken in conjunction with the accompanying drawings.